1. Field of the Invention
The present application relates generally to aircraft engine performance, in particular, to a Digital Engine Control system.
2. Description of Related Art
Digital engine control systems have been around for many years. Digital engine control systems are typically used to control aspects of aircraft engine performance, such as fuel flow and rotor speed, for example. As operating conditions vary for the aircraft, rotor speed may increase or decrease. Digital engine control systems typically operate so as to maintain a relatively constant rotor speed by adjusting the fuel flow to the engine. However, adjusting the fuel flow to maintain constant rotor speeds may decrease the engine power generated.
Traditionally, hydro pneumatic engine control systems were heavily damped and did not control rotor speed with tight tolerances. As such, slight increases or decreases of rotor speeds did not trigger the hydro pneumatic engine control systems to modify fuel flow. More recently, digital engine control systems are generally more tightly monitored. Typically, slight increases or decreases of rotor speeds trigger the digital engine control system to modify fuel flow and therefore engine power.
Reducing engine power by maintaining constant rotor speeds may have negative implications. For example, during fixed collective take-offs in certification tests, a decrease in engine power may cause the helicopter to lose too much altitude, thereby unsuccessfully performing a certification requirement. In order to compensate for the digital engine control system, a pilot may manually increase engine power. However, increasing power may negatively affect the aircraft's IGE hover performance.
Although great strides have been made in digital engine control systems, considerable shortcomings remain.
While the system and method of the present application is susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and are herein described in detail. It should be understood, however, that the description herein of specific embodiments is not intended to limit the application to the particular embodiment disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the process of the present application as defined by the appended claims.